Monday, June 18, 2012

More on the "Oooh"... the FlexRadio 6700

Being a computer geek, through and through, since returning to the amateur radio fold a few years back I confess to being a little underwhelmed by the state-of-the-art in radio hardware.

The top of the line transceivers certainly represented the best analogue/radio circuitry that contemporary electronics could offer. With super-stable oscillators and clever low-noise designs analogue radio had made great strides. However, despite many innovations including some digital signal path and transceiver control these radios were still 'classic' in so many other ways.

Journey around the back of most radios and you are still greeted with a myriad of single-purpose analogue interfaces. OK, the antenna connections are a mandatory, physical, analogue connector, but there are also discrete analogue audio in/out, PTT and control connectors - with few industry (only vendor) standards.

A few of the more recent (and expensive) radios sport digital interfaces: USB, SPDIF and maybe even RJ-45 ethernet. However, when you look at the specs, these interfaces often have very specific functions intended by the vendor. The only real value of the ethernet on the IC-7800 for example is to upgrade the firmware.

Frankly, if you use a computer with your radio (and how many of us don't use one in some capacity), then interfacing the computer and radio is often a nightmare. As noted, there are distinct connections for specific parts of that interface: CAT for control, analogue audio in and out lines that need to be connected to sound cards and have their levels correctly set. There may be PTT relays to configure, or alternatively the transmitter can be audio keyed with various tweakable delays. On the computer, there are RS232 interfaces to configure, but who uses RS232 these days!!. If you don't have native RS232 on your computer then you have to configure USB-serial bridges. You might have to set up 'virtual COM ports' and manage these in the operating system and possibly every element of radio software you want to use. What a mess.

I always wanted to find a radio that:

Was engineered with no-compromises in the inevitable analogue/radio side

Had as much as possible of the signal path handled in the digital domain (and with configurable digital 'circuitry' implemented in modern FPGA and DSP hardware).

Presented as general as possible a connection to a computer, so that all facets of a radio (input audio, output audio, transceiver control) could be handled on a single interface with a appropriate, extensible communications protocol.

For me physical knobs and switches on the actual radio are not an essential. I know they are for some operators, but these are not mutually exclusive with full digital control of the rig. In any case, I really do not think having a physical interface forgives poor computer interfacing in a modern radio.

So, what I've been looking for is a radio with:

A super high-quality direct conversion SDR design

An industry-standard high-bandwidth, general purpose computer interface (Firewire OK, Thunderbolt better because of sheer bandwidth, Gigabit Ethernet probably best because of good speed and allowing the radio to be a networkresource).

A powerful, reconfigurable digital signal path. To allow for upgrades to the digital side of the radio 'hardware' as well as to enable more flexible operator interfaces such as multi-slice panadapters.

A well-specified, extensible radio-to-computer connector/network protocol. Allowing all the functions of the radio to be accessed programmatically and remotely from the computer or network and supporting realtime digital audio streams to and from the radio at all times.

Great client software for operating the radio on a computer... oh, and preferably for that software to run on a Mac as my own preferred computing environment.

A reasonable 'brand' behind the radio, so that you can trust the design, quality and support that you might need. After all, software has bugs, power transistors fail, etc.

I've watched the emergence of the SDR industry with much interest and have almost been tempted to jump in at various points (even thinking about just getting a receiver to complement my 7800 on transmit). However, I've never been completely convinced with any offering to date.

FlexRadio's 6700 has me convinced now however.

The 6700 has the potential to meet and even exceed my 7800 in just being a radio, but importantly I think it completely transcends the 7800 in terms of being a radio platform. This hardware is absolutely a foundation on which FlexRadio can continue to both optimise and innovate in the years ahead, plus it decouples the client interface (and some processing there) in the computer, allowing that component of the system to improve somewhat independently at its own rate.

When I bought my 7800, although the radio had been in the market for several years already, I had a vain hope that Icom would continue with regular innovation on this, their flagship transceiver. While to their credit they have produced a fairly steady stream of updates to fix defects and add very tiny features, it's a fairly safe bet that they aren't going to do anything radical and new. My biggest hope was that they would make the ethernet port genuinely useful and a 'complete' interface for the radio along the lines of the above, but I sincerely doubt we'll see this. Even their top-of-the-line radio is becoming legacy as analogue components (with their associated optimal designs) and especially digital components, improve. At some point, possibly already in the past, they will reason that further research and development will not translate to much better revenues from the product and they have to move on to a new flagship.

As a radio platform, the 6700 has so much more of its architecture expressed from general substrate (FPGA, DSPs, ARM CPUs etc.). With direct downsampling of the RF, so much more of the signal path is implemented with this reconfigurable hardware and we're told that there's enough of this general fabric left over for further elaborations and new features in the future. All this bodes rather well compared with the 7800. A radio that while still awesome and completely relevant, has very few places left to go and rather represents the zenith of its generation, rather than the genesis of the next.

My understanding is that FlexRadio expects to present each owner of pre-ordered brand new 6000-series radios with a callsign-personalised jacket when the radios ship in Q4. I intend being able to wear one of these jackets.